This invention relates to a driving apparatus for driving an optical element (such as an objective lens) used in a device for recording information on or reproducing information from an information recording medium, such as a DVD (Digital Versatile Disc) recorder or the like.
Recently, an optical disk device adaptable to plural kinds of optical disks is being developed. In such an optical disk device, it is necessary to form a beam spot having a suitable shape for the kind of optical disk. Therefore, the optical disk device has a plurality of objective lenses, and is configured to switch the objective lenses in accordance with the kinds of optical disks. The switching of the objective lenses is performed by sliding an entire body of an objective lens driving apparatus (on which a plurality of the objective lenses are mounted) in a tracking direction. Such an apparatus is disclosed in, for example, Japanese Laid-Open Patent Publication No. 9-81947 (in particular, Pages 1 to 8 and FIG. 1 to 6).
However, in the above described conventional apparatus, when the switching of the objective lenses is performed, it is necessary to move relatively heavy weight components (such as a supporting rod and a fixing member) in the tracking direction, as well as light weight components such as objective lenses and a lens holder. Therefore, a large driving force is necessary, with the result that a large-scale apparatus is necessary.